The buoyancy compensator is a vest-shaped device worn about a diver's upper torso to assist in maintaining a diver's buoyancy at a neutral point under water. Within the buoyancy compensator there is an inflatable air bladder. By inflating and deflating the air bladder, the buoyancy of the buoyancy compensator and therefore the diver may be adjusted.
A backpack, on which is mounted one or more pressurized air tanks, is frequently attached to the buoyancy compensator. The backpack rests against the back of the diver, and belting on the buoyancy compensator secures the buoyancy compensator and backpack about the diver's upper torso. It is important for the diver's comfort that the buoyancy compensator and backpack are securely attached to each other and that they both act to conform about the diver's upper torso.
One style of buoyancy compensator is generally formed by an inner and outer lining of polyurethane coated nylon cloth. Each lining has a gas impermeable polyurethane inner layer and a nylon outer backing layer. The two linings are oriented so that the polyurethane inner layers are opposite each other and the nylon backing layers face outward. The inner polyurethane layers are integrally bonded together about the inner and outer peripheral edges of the linings to form a gas tight seal and thereby the inflatable air bladder. The bonding of the polyurethane layers is generally accomplished with RF welding. The backpack is attached to the backside of the buoyancy compensator by means of stitching, belts, fasteners, or the like. An important assembly consideration of conventional buoyancy compensators is that at the attachment point, one or both of the cloth linings may be cut or punctured. To prevent leakage from the air bladders at the attachment point, the polyurethane layers of cloth linings are bonded together to establish an air tight seal which encircles the attachment point.
One of the drawbacks of the prior art buoyancy compensators is the method of attaching the backpack to the compensator. The attachment of the backpack to the compensator by stitching, belting, or fastening, followed by sealing about the attachment point adds costly steps to the construction of the compensator.
An additional drawback of conventional buoyancy compensators is the discomfort the attached backpack may cause the diver. The backpack is generally made of a rigid polymer, and the part of the backpack which interfaces with a diver's back is generally planar. When the compensator and backpack are securely fastened to the diver, the planar backplate contacts and presses against the generally curved back of the diver, which may cause discomfort.
A further drawback is that when the air bladder within the buoyancy compensator is inflated, the generated pressure generally causes ballooning of the linings. This ballooning is undesirable as it may squeeze the diver and restrict the diver's movements. The ballooning may be lessened by restraining the distance the linings can move apart from each other. One present arrangement for restraining the linings is to bond opposing portions of the two linings to each other or to attach a series of vertical internal restraints to the linings. The restraints are attached to the linings by bonding the restraints to the inner layers of the linings at directly opposing locations. The restraints typically are aligned to each other and placed in that portion of the compensator which extends about the sides of the diver's torso. However, when the compensator is inflated and the frontal portions of the buoyancy compensator are secured about a diver's torso, these types of internal restraints cause the linings to form a planar configuration or flatten out. This flattening out of the vest, particularly in that portion of the vest extending about the sides of the diver, causes so-called "diver squeeze" which is undesirable.
It is therefore an object of the present invention to provide a buoyancy compensator vest and attached backpack which conforms about a diver's torso. A related object is to provide a backpack having a baseplate which conforms to the back of a diver.
It is also an object of the present invention to provide a buoyancy compensator vest and backpack in which the backpack is attached to the compensator vest at the attachment point and is sealed in a single step.
It is an additional object of the present invention to provide a buoyancy compensator having linings which curve about the sides of a diver when the air bladder is inflated.